/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You under the Apache License, Version 2.0
    * (the "License"); you may not use this file except in compliance with
    * the License.  You may obtain a copy of the License at
    *
    *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package org.apache.shardingsphere.data.pipeline.core.ingest.dumper.mapper;
  
  import lombok.ToString;
  import org.apache.shardingsphere.infra.metadata.database.schema.QualifiedTable;
  import org.apache.shardingsphere.infra.metadata.identifier.ShardingSphereIdentifier;
  
  import java.util.Collection;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.Map.Entry;
  import java.util.stream.Collectors;
  
  /**
   * Table and schema name mapper.
   */
  @ToString
  public final class TableAndSchemaNameMapper {
      
      private final Map<ShardingSphereIdentifier, String> mapping;
      
      public TableAndSchemaNameMapper(final Map<String, String> tableSchemaMap) {
          mapping = null == tableSchemaMap ? Collections.emptyMap() : getLogicTableNameMap(tableSchemaMap);
      }
      
      public TableAndSchemaNameMapper(final Collection<String> tableNames) {
          Map<String, String> tableNameSchemaMap = tableNames.stream().map(each -> each.split("\\.")).filter(split -> split.length > 1).collect(Collectors.toMap(split -> split[1], split -> split[0]));
          mapping = getLogicTableNameMap(tableNameSchemaMap);
      }
      
      private Map<ShardingSphereIdentifier, String> getLogicTableNameMap(final Map<String, String> tableSchemaMap) {
          Map<ShardingSphereIdentifier, String> result = new HashMap<>(tableSchemaMap.size(), 1F);
          for (Entry<String, String> entry : tableSchemaMap.entrySet()) {
              String tableName = entry.getKey();
              String schemaName = entry.getValue();
              if (null != schemaName) {
                  result.put(new ShardingSphereIdentifier(tableName), schemaName);
              }
          }
          return result;
      }
      
      /**
       * Get schema name.
       *
       * @param logicTableName logic table name
       * @return schema name
       */
      public String getSchemaName(final String logicTableName) {
          return mapping.get(new ShardingSphereIdentifier(logicTableName));
      }
      
      /**
       * Get schema name.
       *
       * @param logicTableName logic table name
       * @return schema name
       */
      public String getSchemaName(final ShardingSphereIdentifier logicTableName) {
          return mapping.get(logicTableName);
      }
      
      /**
       * Get qualified tables.
       *
       * @return qualified tables
       */
      public Collection<QualifiedTable> getQualifiedTables() {
          return mapping.entrySet().stream().map(entry -> new QualifiedTable(entry.getValue(), entry.getKey().getValue())).collect(Collectors.toList());
      }
  }